Brewster ADU Regulations
Current zoning bylaws, requirements, and permit process for Accessory Dwelling Units in Brewster, Massachusetts. Last updated: October 2025.
Please Note: This information is provided for general informational purposes only and should not be considered legal or professional advice. ADU regulations are subject to change, and individual circumstances may vary. We strongly recommend verifying all requirements, zoning bylaws, and permit procedures directly with the Town of Brewster Building Department or Planning Board before beginning any planning or construction activities. Town officials can provide the most current regulations and guidance specific to your property and project.
Bullet Point Summary
- Maximum Size:900 sq ft or 40% of habitable area of principal dwelling, whichever is less
- Owner Occupancy Required: either principal dwelling or ADU must be owner-occupied 12 months/year
- Number of ADUs Permitted: One ADU per lot; only 20 ADU permits issued per year
- Attached vs. Detached: Both allowed
- Parking Requirements: One parking space per bedroom in ADU
- Design Requirements: ADU must be clearly subordinate to principal dwelling; max 2 bedrooms }
- Septic/Title 5 Requirements: Special permit required for ADUs in Zone II, Herring River watershed, or Pleasant Bay watershed; may require advanced nitrogen treatment systems
- Rental Restrictions: Short-term rentals not allowed; rooms within ADU cannot be sublet
- Special Incentives: None identified
- Application Process: By-right with building permit; special permit needed in certain watersheds
Additional Information
For the most up-to-date and complete regulations, please contact the Brewster Building Department or visit the town's official website.
Our ADU specialists can help you navigate Brewster's specific requirements and design an ADU that meets all local regulations while maximizing your property's potential.